This invention relates to a method and apparatus for recording a reproduction picture having a substantially continuous tone on a photosensitive material by controlling exposure means of the recording section according to a picture signal obtained photoelectrically by scanning an original picture having a continuous tone, for use in a picture scanning and recording system such as a color scanner. More particularly, it is concerned with a method and apparatus for recording a reproduction picture having a substantially continuous tone by utilizing the basic structure of the so-called dot generator wherein a plurality of light beams serving as exposure means of the recording section are controlled to be ON or OFF each independently according to a picture signal in a picture scanning and recording system.
Heretofore, in a picture scanning and recording system such as a color scanner, there have been developed and practically used various means for recording a halftone picture directly from an original picture having a continuous tone. One typical such means employs a contact screen, in which the contact screen is overlapped closely with a photosensitive material disposed on the recording cylinder, and with a light beam modulated according to a picture signal, the photosensitive material is exposed through the contact screen to thereby record a halftone picture. This method, however, involves inconveniences such that the cost is increased because the contact screen originally has a consumable factor and that the halftone dot size is unstable due to the influence of fringe.
In contrast with such a photographic method using the contact screen, there has been developed the so-called dot generator as means for forming halftone dots electrically, and recently such an electrical means has also been spreading to a fairly great extent.
In a typical known system using a dot generator, as disclosed in Japanese Patent Laying-Open Specification Nos. 52-118302 and 52-123701 and Japanese Patent Publication No. 52-33523, a plurality of light beams of the recording section are modulated and controlled to be turned ON or OFF each independently according to a picture signal thereby recording a halftone picture.
On the other hand, in a picture scanning and recording system such as a color scanner it is necessary to provide such a system for the so-called "continuous tone" whereby a reproduction picture having a continuous tone is substantially obtainable as in gravure printing and textile printing in addition to the so-called "screening" whereby a half-tone picture is obtainable directly from an original picture having a continuous tone. At present, such recording system of the type for either "screening" or "continuous tone" is used, or it is used by changing recording heads, depending on purposes of use and objects to be recorded.